A: A de-icer is an important piece of equipment in areas where water features freeze over during the winter. This little device maintains a small opening in the ice, which allows harmful gas to escape into the air allowing for efficient air exchange. It can be the difference between life and death for the fish and other inhabitants in your pond.

Which de-icer is best for your situation? It will depend on how many gallons your pond holds, and if you’re using it alone or with an aeration system.

First, here’s what we recommend for de-icers based on the size of your pond:

These de-icers do a great job, but keep in mind that they can be expensive to run non-stop during the cold months. A 1,500 watt de-icer can cost up to $75.00 to operate. That’s a big bill for a small hole!

That’s where an aeration system comes into play.

Aeration systems – can help maintain a hole in the ice while adding oxygen and are infinitely more energy-efficient than pond de-icers. When used in tandem, aeration can significantly reduce the wattage requirements of your pond de-icer, allowing the use of a smaller 100 watt de-icer. It’ll cut energy costs and save you money all season long. For example a 2,000 gallon pond using the PondAir™ 4 and 100 Watt Thermo-Pond De-Icer will cost $5.40 per month instead of $75.00 using a de-icer alone. Not a bad deal!

When backyard water features are home to year-round populations of fish, it’s vitally important to prevent long-term ice cover. Without a break in the ice, harmful gases produced by decaying leaves and other organic matter build up, threatening the well-being of wintering fish. To prevent that threat, many pond owners install thermostatically-controlled de-icers, which produce enough concentrated heat to keep a vent hole open during winter’s coldest months.

When a de-icer is thermostatically controlled, it is set to turn both on and off at certain temperatures. In theory, that makes good sense: if the water is cold, the de-icer goes to work, and when the water warms, it switches off – saving on unnecessary electricity costs. The problem, however, is that the water temperature in a frozen pond may not rise above the thermostat’s high-temperature shutoff threshold, leaving the de-icer in full heating mode all the time.

Naturally, we’ve given this issue some thought. And that’s why we strongly recommend the use of our Thermo Cube® Thermostatically Activated Plug. Unlike a thermostatically-controlled de-icer, the Thermo Cube® measures air – not water temperature. Thus, when the sun is shining, and air temperatures warm up, the Thermo Cube® automatically cuts power to the de-icer, and turns it back on when the air temperature drops. The combination works flawlessly – applying heat when it’s required to keep the ice open, and shutting it off when it’s not.